Gastrodin Alleviates Cerebral Ischaemia/Reperfusion Injury by Inhibiting Pyroptosis by Regulating the lncRNA NEAT1/miR-22-3p Axis.

Cerebral ischaemia/reperfusion (I/R) injury-induced irreversible brain injury is a major cause of mortality and functional impairment in ageing people. Gastrodin (GAS), derived from the traditional Chinese herbal medicine Tianma, has been reported to inhibit the progression of stroke, but the mechanism whereby GAS modulates the progression of cerebral I/R remains unclear. The middle cerebral artery occlusion method was used as a model of I/R in vivo. Rats were pretreated with GAS by intraperitoneal injection 7 days before I/R surgery and were then treated with GAS for 7 days after I/R surgery. Additionally, an oxygen-glucose deprivation/reoxygenation model using neuronal cells was established in vitro to simulate I/R injury. 2,3,5-Triphenyltetrazolium chloride and Nissl staining were used to evaluate infarct size and neuronal damage, respectively. Lactate dehydrogenase release and cell counting kit-8 assays were used to assess neuronal cell viability. Enzyme-linked immunosorbent assay, qPCR, flow cytometry and western blotting were performed to analyse the expression levels of inflammatory factors (IL-1ß, IL-18), lncRNA NEAT1, miR-22-3p, NLRP3 and cleaved caspase-1. Luciferase reporter experiments were performed to verify the association between lncRNA NEAT1 and miR-22-3p. The results indicated that GAS could significantly improve the neurological scores of rats and reduce the area of cerebral infarction. Meanwhile, GAS inhibited pyroptosis by downregulating NLRP3, inflammatory factors (IL-1ß, IL-18) and cleaved caspase-1. In addition, GAS attenuated I/R-induced inflammation in neuronal cells through the modulation of the lncRNA NEAT1/miR-22-3p axis. GAS significantly attenuated cerebral I/R injury via modulation of the lncRNA NEAT1/miR-22-3p axis. Thus, GAS might serve as a new agent for the treatment of cerebral I/R injury.

Gastrodin combined with rhynchophylline inhibits cerebral ischaemia-induced inflammasome activation via upregulating miR-21-5p and miR-331-5p.

BACKGROUND: The protective effects of gastrodin and rhynchophylline in ischaemic injury have been reported. However, the underlying mechanism and the effect of the combination of these two drugs in ischaemic injury remain unclear. Herein, we aimed to explore the effects of the combination of gastrodin and rhynchophylline on ischaemia-induced inflammasome activation as well as the underlying mechanism. METHODS: Middle cerebral artery occlusion (MCAO) mice and oxygen glucose deprivation (OGD)-treated BV2 cells were used as in vivo and in vitro models of ischaemia, respectively. Cerebral injury was determined by TTC staining, H&E staining and neurological deficit scores. The effects of the combination of gastrodin and rhynchophylline on inflammasome activation were measured by the MTT assay, Western blotting and ELISA. The expression of miR-21-5p and miR-331-5p was measured by qRT-PCR. The potential binding between miR-21-5p and TXNIP and between miR-331-5p and TRAF6 was analysed with Targetscan and a luciferase assay. RESULTS: MCAO-induced tissue infarction, neurological deficits, inflammasome activation, and downregulation of miR-21-5p and miR-331-5p were all mitigated by the combination of gastrodin and rhynchophylline. In OGD-treated BV2 cells, the combination of gastrodin and rhynchophylline also alleviated inflammasome activation and restored the expression of miR-21-5p and miR-331-5p. TXNIP and TRAF6 were confirmed to be targets of miR-21-5p and miR-331-5p, respectively. Moreover, OGD-induced inflammasome activation was attenuated by the overexpression of either miR-331-5p or miR-21-5p and was further attenuated by the overexpression of both. Finally, we demonstrated that a miR-21-5p inhibitor and/or a miR-331-5p inhibitor counteracted the protective effects of gastrodin and/or rhynchophylline. CONCLUSIONS: The combination of gastrodin and rhynchophylline exerts neuroprotective effects by preventing ischaemia-induced inflammasome activation via upregulating miR-21-5p and miR-331-5p.